What
Is Cognitive Task Design?
A
Practical View
Every artefact that we design and build has consequences for how it is used. This goes for technological artefacts (gadgets, devices, machines, interfaces, complex processes) as well as social artefacts (rules, rituals, procedures, social structures and organisations).
The consequences for use can be seen both in the direct and concrete (physical) interaction with the artefact (predominantly manual work) as well as in how the use or interaction with the artefact is planned and organised (predominantly cognitive work). Thus, introducing a new tool not only affects how work is done, but also how it is conceived of and organised. This will in most cases have consequences for other parts of work, and may lead to unforeseen changes with either manifest or latent effects.
The primary target of design is often the direct interaction with or use of the artefact - as in Human-Computer Interaction and Human-Machine Interaction. Interface design, instruction manuals and procedures typically describe how an artefact should be used, but not how we should plan or organise the use of it. Yet the realisation of the artefact may affect the latter as much or even more than the former.
As a definition, the aim of Cognitive Task Design is to focus on the consequences that artefacts have for how they are used, and how this use changes the way we think about them and work with them on the individual as well as organisational level. The ambition is to ensure that Cognitive Task Design is an explicit part of the design activity, rather than something that is done fortuitously and in an unsystematic manner.
The Meaning Of Cognition
The terms cognitive and cognition have generally been used without much precision. It is therefore necessary to provide a more precise definition of what cognition means, although this is far from easy since etymology, semantics, and practice may be at odds with each other. In relation to CTD, the following line of reasoning is applied.
Cognition is a term used to describe the psychological processes involved in the acquisition, organisation and use of knowledge emphasising the rational rather than the emotional characteristics. Etymologically it is derived from the Latin word cognoscere: to learn, which in turn is based on gnoscere: to know. Cognitive tasks could therefore simply be defined as those tasks that require or include cognition.
This easily leads to an axiomatic position, which starts from the fact that humans are cognitive beings (or that humans have cognition), hence that human performance has a cognitive component. However, following the same line of reasoning one could also argue that human actions are driven by motives and emotions, and that human performance therefore has a motivational and an emotional component which indeed it has. While it is evidently true that humans have cognition, the axiomatic position makes it difficult to extend the notion of cognition to other entities, such as technological artefacts and organisations. It also begs the question of what cognition really is.
An alternative is to use a more pragmatic definition, which is based on the characteristics of certain types of performance. Human performance is typically both orderly (systematic and organised) and goal directed. This can be used as a provisional definition of cognition, and be extended to require that cognitive tasks have the following characteristics:
Cognitive tasks are driven by goals (purposes, intentions) rather than by events. They include cause-based (feedforward) control as well as error-based (feedback) control. Cognitive tasks are therefore not merely responses based on algorithmic combinations of predefined elements, but require thinking ahead or planning over and above complex reactions.
Cognitive tasks are not limited to humans; cognitive tasks can be found in the functioning of organisations, of certain artefacts (a growing number, but still not many), and of animals.
Polemically, the issue is whether the definition of cognitive tasks is based on an axiomatic definition of cognition, or a pragmatic characterisation of performance. In other words, cognitive tasks could be defined as tasks performed by a system that has cognition which presumably only humans have(?). Alternatively, cognition could be defined as a quality of any system that has certain performance characteristics, and which therefore can be said to do cognitive tasks. This would base the definition on the characteristics of the tasks and of system performance, rather than on the possible constituents and explanations of internal mechanisms.
From this perspective, cognitive tasks are characteristic of humans, organisations, and some artefacts - leaving out animals in this context. Cognitive task design is consequently concerned with how functions and structures of a cognitive system proper and of its environment can be designed to further the systems ability to perform in a purposeful manner and to let it keep control of what it is doing. Looked at in this way cognitive task design refers to (joint) cognitive systems as a whole, whether they are biological individuals, artificial intelligences, or organisations. Cognitive task design clearly also goes beyond cognitive tasks analysis, as the emphasis is on the potential (future) rather than the actual (past and present) performance.
The importance of cognitive task design stems from the fact that any change to a system such as the introduction of new technology, improved functionality, or organisational changes inevitably changes the working conditions for the people in the system, hence their cognitive tasks. All design is therefore implicitly or explicitly cognitive task design. This is obviously the case for technological artefacts and information devices, since these directly affect user tasks. A little thought makes it clear that the same is true for any kind of design or intentional change to a system, since the use of the system, i.e., the way in which functions are accomplished and tasks carried out, will be affected. Cognitive task design comprises the study of how intentional changes to system functions and structures affect the conditions for work, hence on the cognitive tasks, and the development of concepts and methods that can be used to improve design practices.
The outcome of this line of reasoning is that cognition is not defined as a psychological process, unique to humans, but as a characteristic of system performance, namely the ability to maintain control. Any system that can maintain control is therefore potentially cognitive or has cognition. In this way the focus of cognitive task design is not just on the characteristics of putative human information processing or capabilities such as recognition, discrimination and decision-making that normally are seen as components of cognitive work. The focus is rather on descriptions of the performance of cognitive systems in the complex sociotechnical networks that provide the foundation of our societies, and how this performance must change to enable the systems to stay in control. CTD therefore struggles with the dilemma known as the envisioned word problem (Woods, 1998), i.e., how the results of a cognitive task analysis that characterises cognitive and cooperative activities in a field of practice can be applied to the design process, since the introduction of new technology will transform the nature of practice! Or put more directly, the paradox of CTD is that the artefacts we design change the very assumptions on which they were designed.
Hollnagel, E. (2003) (Ed.), Handbook of cognitive task design. Mahwah, NJ: Erlbaum.
Woods, D. D. (1998). Commentary: Designs are hypotheses about how artefacts shape cognition and collaboration. Ergonomics, 41(2), 169-173.